The present invention relates to a slide closure arrangement for the tapping of metallurgical vessels or furnaces, such as tipping converters and furnaces of the type including a flange provided on a tapping connection and an annular ring-shaped plate attached thereto to close the refractory lining at the connection of the tapping area.
It is well known that it is difficult to obtain a clean separation of the molten metal from the slag floating thereon in converters or tipping furnaces. In most cases, and especially toward the end of a tapping operation, either the slag passes into the ladle together with the molten metal, or the molten metal passes together with the slag into the slag-collecting crucible, since the converter cannot be raised with sufficient swiftness from the pouring position when the flow through the tapping connection changes from molten metal to slag. Until the present time it was not possible to attain an economical emptying of the converter together with a clean separation of molten metal and slag.
The above problem is considered to be solved in principle by the arrangement of a slide closure on the tapping connection of converters or furnaces. Such closure is customarily used on the spouts of metallurgical vessels, since the closure allows a prompt interruption of the tapping operation, so that the molten metal and the slag can be accurately separated.
However, the above solution is associated with a series of considerable difficulties, especially on blast steel converters, in particular in view of the required replacement of the refractory parts of the slide closure which are subjected to wear and the service life of which between replacement operations is relatively short. For example, the operation of a larger converter lasts about thirty days at the rate of approximately thirty daily charges. During such operation, the primary duty of the steel worker at the present time is to maintain the converter failure-free in operation.
Due to the conditions under which converters are presently operated, it may be expected that the slide closure parts subjected to wear must be replaced after approximately thirty charges, i.e. once daily, and the entire slide closure inclusive of the hydraulic drive must be inspected and overhauled once a week. This necessarily results in interruptions of the converter operation. Such interruptions, particularly considering the time required to repair the present slide closure arrangements, are unacceptable, especially since repairs cannot be undertaken on a slide closure while attached to the converter, due to the intensive thermal radiation of the tapping connection.